Calcium oxalate crystals mediated choice and feeding of whitefly, Bemisia tabaci in weeds

Crystals may modify the food quality, reduce a plant palatability, and choice to insects, or defend against pests. Bemisia tabaci (Genn.) (Hemiptera: Aleyrodidae) is considered one of the most damaging pests in field crops in the world, and is usually associated with several hosts. We examined relations between the choices of whitefly with calcium oxalate crystals (COC) presence in weeds. The treatments were weed species Amaranthus viridis L., Amaranthus viridis L., Bidens pilosa L., Chenopodium album L., Nicandra physalodes L., and Solanum americanum Mill., and, as control, Brassica oleraceae var. capitata L. B. tabaci infestation was evaluated at 7, 14, 21, and 28 days after infestation (DAI), the height and shoot dry mass at 28 DAI, and leaf blades were prepared from all treatments. B. oleraceae var. capitata, S. americanum, and B. pilosa showed greater B. tabaci infestation in this order, respectively. In the presence of COC, the reverse occurred, since in these plants there was a lower presence of COC. It is concluded that the presence of COC influences B. tabaci preference in the choice of its hosts.